Weight scales have been constructed which include a base and an upstanding column thereon plus an indicator at the top of the column with this weight scale being all mechanical. A load receiver may be termed a platter, a platform, or a pan in different scales, and was movably mounted on the base to act through a lever system to pull on a stress rod. This rod was often called a steelyard, and mechanically acted on the indicator. In more recent years electronic scales have been utilized wherein the indicator was an electrical indicator and a force-to-electrical output transducer was mounted in the base to be acted on by the lever system which was connected to the load receiver. Electrical conductors then interconnected the transducer in the base and the indicator in the housing on top of the column.
Such electronic scales were useful in a protected environment where they were not subject to corrosive gasses or splashing liquids. However, many scales are used in an industrial environment, such as in food processing plants, wherein the plant is washed down with water spraying hoses perhaps once a day. Other industrial scales may be used in chemical plants such as fertilizer plants, with the area being washed down perhaps only once a year, nevertheless, splashing liquids can strike the scale at such time. The prior art has known of electronic scales which are resistant to such washdown situations. To accomplish this the prior art provided a transducer with a water tight compartment surrounding the transducer and with any covers sealed with a gasket. The electrical connection was through a water tight plug and cable connection, often potted in some hardened plastic to be water tight. Also, the transducer had to have some form of mechanical motion input from the lever system and this was often made water tight in some way, for example, by a flexible bellows at the point of force actuation. Such protective covering to make the transducer and its electrical connections and mechanical connections water tight added considerably to the complexity of the electronic scale and of course increased the cost of such splash-resistant scale.
There are thousands of mechanical scales still in use in the field with the base and lever system still in good working order. Such scales might be converted to electronic scales but then they would not be splash resistant.
The problem to be solved, accordingly, is how to provide a splash-resistant scale in a simpler and more economical manner without necessity for the water tight compartment for the transducer, the water tight but flexible connection to the force application point, and the water tight electrical connection to the transducer.